A Sailor's Secret (A Undertale OC AU)
by AshWrites17
Summary: Seraphim Ariella was just a normal citizen of the mainland... Having heard stories of pirates around her area, she finally took her moment to leave her Noble life and began living as a pirate. Wish Gaster was the captain of the most feared pirate crew on the seas. Running the ship wasn't hard until she showed up begging for a job... This is a love story like no other.
1. Chapter 1

"Just let me on! Please!" The young woman cried, standing in front of a large pirate. The pirate crossed his arms and frowned at her, glowering down at her.

"Not. Without. Captain's. Approval." He had been repeating this statement to her, but she didn't want to give up. She HAD to get on that ship.

"Well, where's your damn captain then?" She growled at him. Even though the pirate was double her size, and human at that, she had to assert some kind of dominance. Her torn pink dress and protruding corset didn't do any favors for her, though.

"He's on his way. I've told you this a dozen times, little lady." The human pirate was dressed in the familiar red and gray uniform of the pirates on The Coveted. They were the best pirates out there, and she desperately needed to get on that ship before her father found her again.

"Well, he needs to hurry! I can't wait for much lo-" Her sentence was cut off by a growl next to her from behind. She turned her head slowly and gasped when she saw the face.

There he was… The captain… The most feared person on the mainland. Right behind her, staring at her with those infamous red and gray eyes.

"What's going on here?" He growled, his voice showing no emotion. It was dark and raspy, with the low New-York accent.

"This little… girl." She growled at the pirate's insult to her. "Wants to board our ship."

The captain frowned. He walked in front of her, looking down at her with the same antagonizing glare he gave everyone.

"What's your name, girl?" He asked.

"Seraphim Ariella, sir," Sera said, straightening up to look at him. Her confidence didn't waver once as she stared up into his eyes. He raised an eyebrow curiously, watching her carefully.

"I assume you know my name." He said, placing a hand on his hip. Sera nodded quickly.

"Yes. Wish Gaster, captain of The Coveted." Sera knew as much as anyone could know about this band of pirates. Wish nodded slowly.

"Why do you want to board my ship? Transport? Protection?" Wish said, walking around her agonizingly. Sera shook her head quickly.

"I want to be apart of your crew." She said. "I want to work as a pirate. I want to be a pirate."

"A female pirate?" Wish scoffed and snickered. "Have you ever heard of a female pirate, Ms. Ariella?"

Sera shook her head but smirked up at Wish, her demeanor confident and set. "No, sir. But I can do whatever you need me to."

Wish raised an eyebrow curiously. After a moment he smirked and nodded to the pirate who had been keeping her from entering.

"Chess, let her in. We'll REALLY test her." Chess smirked and nodded, moving out of the way. Wish chuckled, walking ahead.

Chess walked behind Sera as she followed the captain. The captain walked with his head held high, his large hat tipping over his eyes.

"What does he mean 'really test' me?" Sera looked back at Chess, and he was still holding that sinister smirk.

"If you fail this test you'll die, little lady." Sera's eyes widened a little but she nodded with a small smile.


	2. Chapter 2

Their small party walked onto the main deck of the ship, and it was a sight to see. The entire crew mingled and talked and worked, some laughing and dancing, others working ropes or singing. But the second Wish stepped foot on the deck, the party slowly went silent. All eyes fixed first on the captain, and then onto Sera. The men seemed curious, some even a little bit hostile. Wish walked a few more steps, the larger human pirate stopping with Sera before he turns. His smile was a little bit sinister, but his eyes glittered with a sort of dark humor.

"Boys, I have a special guest I'd love for you to meet. Miss Seraphim Ariella! This pretty little lady has requested… that she joins the crew!" He raised his eyebrows at the crew for them to share his surprise, and they laughed, jostling each other jokingly. He raised his hand again and they quieted

"Now, of course, I will give credit to the little lady for her bravery. Making a request like that, and for a crew like this of all..." He whistled appreciatively, nodding to Sera with his obnoxious smirk. "You've got iron guts, miss. But I wonder, what experience do you have that would be fit for a crew like this?"

Sera scoffed at the attitude from Wish, crossing her arms over her chest with an annoyed frown. "Patronize me all you like, captain." She smirked a little, staring directly into his eyes. "Do you remember the first war against the humans, a war that we monsters won?" Wish nods, his eyes narrowing. The crew raised their eyebrows at Sera as if reevaluating their impressions of the girl

"I do. Fought in it myself. In fact, most of my crew are retired war dogs… what of it?" Sera smirked, uncrossing her arms and placing one on her left hip.

"Ever heard the tale of The Cloaked Barron? The one that terrorized human villages, slaughtering their men and taking their children hostage until the war was won?" Wish nodded trailing his fingers down the hilt of his four swords strapped at his side as if anticipating using it soon.

"Yes. He burned a path through most of the war turf before the monsters managed to win. But you haven't answered my question. What significance is it?"

"There was one man who saw the Cloaked Barron take off their cloak. He cried "he's a girl! A lady!" to anyone who would listen, but everyone refused to believe him. Ladies don't fight." She reaches into a satchel lying gently on her hip, pulling out a tattered night-black cloak. "This belonged to her. I am the Cloaked Barron."

The crew went silent, shifting uneasily. They looked at Wish as if waiting for his verdict. The captain waited for a moment before suddenly throwing his head back and laughing. The crew seemed startled, but no one laughed with him. He inclined his head again, his grin monotonous at this rate.

"Miss, any lady can pull out a black cloth and claim to be a war hero. You wanna prove that?" He draws two of the four swords, one curved jagged blade in each hand, his men backing up nervously. He nods to one of them, and they draw their own sword, a basic length of folded steel.

"Take the blade… if you can even stand your ground against me, I'll let you join. Beat me..." His smirk returns, mischievous, conspiratorial.

"I'll even make you my first mate… help lead the crew. What do you say?" The crew shifted uneasily, the sailor holding out his sword glancing nervously from Sera's face to her cloak to the captain and back again.

Sera rolled her eyes, hooking the black cloak upon her shoulders. She waved her hand at the sailor as if saying no. Her hands reached into her cloak and dress, pulling out a singular red-tinted sword that went down to her calf. She looked up at Wish, nodding as she pulled the hood up over her face.

"Let's get started then, captain." Wish growled darkly, his left eye turning to a slit, and stalked forwards slowly. He swung his two swords at his sides, curls of blood-red water starting to seep through the floorboards around his feet.

"The ocean itself is an extension of my weapon, little missy. You're fighting daemonium in domum suam super congestum caespite culmen~" His Latin tones rolling through his teeth, through his smirk.

"That's cute. Relying on a crutch to win? My how the great have fallen." She snickered a little, her entire body illuminated in a purple glow. Her blade seemed to contort and mold until it was at a similar length to Wish's. Through the hood, you could see Sera's left eye glowing purple, her right flashing a multitude of different colors. "Stop antagonizing me and fight, piss ant." He growled again and stepped to his right, his body flickering before he suddenly appeared on her right, his blades poised sideways. They crossed like scissors, slashing from her right shoulder to her left hip.

Sera's body flickered like a reflection in a wave, dropping back as her right eye glowed a little brighter than the left as she took her turn, swinging her blade towards his neck harshly, like that of an assassin's blade. The swing was silent and swift, fast and quick. Wish's own blade came up to catch it, and his eyes narrowed slightly. He pressed his weight into the cross before bringing up his other blade, throwing Sera backward before jumping back into the air. He twisted, the third blade at his waist coming free, and a swirl of water flows up to meet him, pushing off of him as he kicks the sword. The blade flies point first, right for her.

Once Sera landed on the ground again, she looked up to see the blade. She frowned and hummed a single note, sending a blast of sonic energy through her red blade by swinging it. The sonic energy knocked the blade out of the way, Wish's blade instead finding itself lodged in a nearby mast. She then, without hesitation, launched forward and pushed her blade to hit Wish, the point flying forward with her aiming it as the two go.

Wish smiled a little, spinning as he pushed the blade aside on his palm, bringing his two swords down, one on the underside of her handguard, the other keeping the point of the metal away from his chest, and locking her blade in between. He leaned in, their faces a few inches apart as he pressed her backward slowly

"Little lady, decided to play in the big leagues~ Didn't know what she was getting herself into~ No shame in giving in, ya know~" Sera rolled her eyes, glaring darkly at Wish as she pushed him off. She stood upright and smirked, regaining her composure.

"I held my ground against you. I'm apart of the crew. But I'm not one to back down so easily." She poised her sword in front of her, carefully rolling her shoulders back. "Cmon, this can't be that hard for you. This is child's play." Wish raised an eyebrow, smirking at his crew

"Well! Little missy wants something to match her skills!" The other crew members laughed, jostling each other apprehensively as if wrestling for a better view of the fight.

Sera rolled her eyes again, looking at Wish with a taunting smirk. "Well, if this is too hard for you, there's no shame in giving up~" She suddenly disappeared, her body flickering carefully behind Wish. "Or you could actually fight me, like a proper captain~ Would be a shame if I had to… Take over for you~ You're so incompetent~" Her blade was jabbing harshly at his lower back as she growled in his ear. Suddenly, the air changed. There was an audible snap against the back of Wish's neck, like the last rusty spring holding his anger in check had snapped. He thrust his blades up, forcing her blade into the air, whirling around and before she could react, slamming his foot into her chest, sending her flying. The crew started to back away from the fight, fear now in their eyes. Wish's cat slit was expelling a blazing trail of dark grey magic that flickered in the wind like a candle flame. Water started rolling over the sides of the deck, swirling around his feet, rising with his anger

"You are pathetic… you wield a cloak and pitiful excuse for a blade against hapless farmers and think of yourself as a warrior. Well allow me to shed some light on the world for you, child..." His voice was a trailing snarl now, a trail of water reaching up and pulling his other sword from the mast.

"No amount of confidence will replace raw skill, and you're just a scared little house girl run away from home. You would dare insult the captain whom you wish to work for? Then allow me to set the standard..." He tossed his two blades into the air, drawing the other two, and caught on in his mouth, another in the crook of his right arm, Killer B style. He crouched carefully, his face a mask of cold calculating rage.

Sera's eyes widened as she leaned up against the wall she hit, panting hard. But her confidence didn't waver, standing fully upright. She held her hand out towards where her blade flew, and it flew handle first right back into her hand. The atmosphere around her changed. It was darker, and you could tell she was PISSED. Sera wasted no time in using calculated movements to rush Wish with dozens of attacks at once, hitting with her sword then attacking with small sonic blasts here and there.

"You. BASTARD!" From the way it looked to outsiders, Sera was fighting with pure rage. But in reality, she was harnessing her rage to certain attacks, focusing carefully. From what Wish could see, her eyes under her cloak were glowing VIOLENTLY, the different colors were almost blinding. Her attacks were silent and swift while also violent and harsh. And she wasn't losing any energy.

Wish's eyes pressed up as if to smile, and the moment her strikes reached him, he started spinning, jumping, twirling through the air, his swords flying around him, parry, strike, block, counter-attack, thrust. The entire fight, Sera's eyes strained to track all four swirling blades. On top of turning to face him, as he bounded across the deck around her, he was a blur. His posture seemed at ease, but his eyes blazed with concentration, and something else… she realized it was a grudging admiration. Throughout the interaction, they both landed blows, small scratches, scrapes, nothing major. But at one point through the fight, Wish let all four of his blades fly towards Sera like arrows as he launched himself backward, skidding to a stop on his knees twenty feet back. He clapped his hands together and the water around the deck suddenly surged, moving to crush her in a tidal wave-like motion.

Sera smirked, flickering out of the way of the blades. The next time Wish sees her, she's running straight for the wave, diving in quickly. Just for a moment, it seemed like she wouldn't come out. But suddenly she appeared once again behind Wish, using her foot to knock him to the ground, placing her knee harshly in between his shoulder blades, positioning her blade to the back of his neck. She panted harshly, and her clothes were dripping wet all over, but she felt triumphant.

"Watch what you say, captain. You don't want to offend a lady, or you'll end up face down in the dirt." Her words were breathless, but she held there strong. The crew stood in shock for a moment before Wish started to laugh

"It's a funny thing victory… like a fine silk carpet, it can be ripped out from under you when you least expect it~" He flickered and without moving, an arm grappled your waist, literally throwing you full force across the deck. When Sera landed, she saw a clone of Wish standing above the original. He helped the original captain up, who was now battered and covered in various cuts, same as Sera. He brushed off his long cloak and smiled, the clone disappearing. His blades floated up to him and he slipped them into their sheathes. The crew finally let out a collective exhale, as if this was Wish's signal. He raised his eyes to Sera again, and she could see his eyes were back to normal, not nearly as sarcastic or cynical. But he gazed at her with a look of respect. He nodded his head, holding a hand out to his crew

"Well, men. I think Seraphim has proved herself. Any objections?" Nobody moved. Nobody raised a hand. In fact, a few of them even smiled, like this could be a pretty positive change for the crew. Wish waited for another moment before raising his hand straight up

"First mate! Front and center, if you would be so kind." Then there was a nervous ripple through the crowd, and the door to the bottom deck opened. The sailors parted to reveal another skeleton in a knee-length black cloak, blue breaches, and a white button shirt. A rusty pendant was clipped to the chest of his coat, a ribbon hanging under the silver medallion showing the red and grey colors. He held six pistols, three holstered on each leg, and one big one holstered to his chest. He looked up under the brim of a hat only slightly less extravagant than Wish's with its feather and brim, and you could see glowing blue tear tracks running from his eyes. It was Ganz, his gaze cold and piercing. When he seemed to notice Wish's condition, with his cuts, and Sera looking similar his eyes widened. He seemed to understand almost immediately and set a hand on the hand cannon on his chest.

"My captain. A newcomer? A woman?" Wish nodded, placing a hand to his shoulder.

"Our new first mate, first lieutenant Ganz." For a moment Ganz seemed like he would be offended, but he smiled as well, taking his hat off. He walked to Seraphim and offered the hat with a slight head bow.

"For the record, Miss," he said, his smile mischievous, "I'm pleased to see a woman replace me than any of these louts." The other men laughed, a few nodding along.

Sera smiled a little, nodding to Ganz. Her eyes shone with respect and admiration as she took the hat gingerly in her hands.

"Thank you. I hope to do as well as you have." She stood proudly, smiling widely. This was more than she wanted, but she wouldn't complain. This was a dream come true. Ganz smirked a little as he straightened, adjusting his coat

"Well, I hope to see you do even better than I have." He nods once more time to her before walking back to the captain, turning and standing at his side. Wish smiled a little bit more, addressing Sera directly

"Well. How about we let our new first mate get comfortable. You lot are free to go. Be back by dawn on the morrow, or our new member might have to come after you herself." He laughed, and a nervous chuckle rippled through the ranks, but they dispersed, heading off the gangplank and onto the shore. Ganz didn't leave however and simply nodded to the captain before going belowdecks, leaving only the two of them on deck.


End file.
